Ramdisk

[Eelix]

With current ram prices having hit an all-time low why isn't there any more mention of using ramdisks?
32gb of high performance memory cost as little as 250€, making say a 24gb ramdisk easy and cheap to realize.

Benchmarking a ramdrive appears to be more an exercise in testing benchmark programs and filesystems that are unsuited for a throughput flat out off the scale (many of the benchmarks have to be run in multiple parallel instances before the individual measurements significantly degrade), making even the best ssd's look s-l-o-o-o-o-o-w. And that's with freeware drivers, most having not been updated in ages.

Even volatility is hardly a serious issue with implementations of loading and saving disk images at startup and shutdown. (especially when loading from an ssd).
So ... why isn't there anything? No marketability for a pure software implementation? Using bog standard ram ought to annihilate things like caching ssd's in performance.

 

[RetiredChief]

Ram drive, free for upto 4 gigs, $15 for > 4 gigs . I have an 8 gig ram drive set up that I can turn on/off as needed. Have 16 gigs of ram.
http://memory.dataram.com/products-and-services/software/ramdisk
Yes, AS SSD will show about a 10x performance boost over an SSD. SSD = Model T ford, Ram Disk = 2011 sport car.

1) Most systems max out at 16 gigs ram an can only move up to the 32 gig limit if 8 gig modules, expensive compare compared to 4 gig modules.
2) Not sure I'd want to have the image stored on an MLC SSD due to the High write cycle. In my case that would be 8 gig write everytime I cycled the system. If you have the periodic Backup enabled the write cycles could go thru the roof. Would recommend a small SLC drive for storing the image.
3) If image is on a HDD, then Both Boot Time and shut down time are increased. Not really an issue in 24/7 operation, or if you turn on in AM and Off at night. Could be an issue if you periodicly cycle during the day.
4) Size could be a limiting factor for editing/encoding very large Video files such as bluray where a single file can be upto 40 gigs (typically 13-> 25 gigs). Would be ok for DVDs where file size is 1 gig per vob file (6 to 7 gigs for entire movie). For gamers, not sure but probably could install maps here whit almost instant load time.

My first Ram disk was with a 386SX system MAX MEMORY = 1 MEG, kind of limited the size of ramdrive.. Back then you could not save the image, so lost everything if powered off (ie lock up and used the 3 finger salute to reboot). My first store bought 386-sx was a rare exception. Could reboot and ramdrive would still be intack, Untill I need to update the Rom Bios (replace the socketed two chips. Would not except new chips and sent it back for repair. After repair, lost ramdrive with a reboot - LOL.

 

[a4mula]

I'm currently using a 1GB Ramdisk for certain tasks such as temp files, internet cache, page filing. The question I have is can you use a Ramdisk for HDD caching purposes much like Intel is doing with SRT and SSDs? If so, can you provide a link that instructs a person on how to set this up.

 

[Eelix]

The question I have is can you use a Ramdisk for HDD caching purposes much like Intel is doing with SRT and SSDs? If so, can you provide a link that instructs a person on how to set this up.

It's definitely doable, but the only implementation I know of is Superspeed's. It's expensive though and no idea how well, if well at all, it performs. Just google for superspeed supercache and you should find it, they have a fully functional trial version available. Maybe you can try it out and tell us how it works?

I'm looking to buy an -E setup since my current one has just about reached the end of its useful lifespan and since ram amount and performance is really no issue at all there, I guess my post was a bit of a rant about no ramdisk drivers or filesystems that are remotely suitable for a current system like that.
Not that I know of any disk benchmark programs that aren't left gasping in the dust even by older implementations and far less capable systems. Are there any?
There's almost no data available that isn't years out of date and wildly inaccurate to boot.
It'd almost be worth it to make a little DIY roundup.

 

[andywork78]

more then 4GB memory base one use 1~2GB ramdisk.
Make sure temp and history cache is on ramdisk.
your pc is fly~ fly~

 

[Idonno]

SuperSpeed SuperCache works great! I've only been using it a couple of days but I'm impressed. I already had a 4GB RamDisk dedicated to Paging as my only pagefile for all disks and that in itself was pretty impressive performance wise, that completely eliminated all micro-stutter from my HD6870 crossFire set up.

A few days ago I added a 8GB RamCache (SuperSpeed SuperCache). The way it works is it dedicates the amount of ram you choose to a specific disk for a cache. I dedicated it to my sata II SSD raid 0 array that runs my OS and programs. The increase in speed and performance is very noticeable.

I have 24GBs of ram 4 for my RAM pagefile, 8 for my RAM Cache and 12 left over for the OS. If you have enough ram try it. It definitely makes a bigger difference than I thought possible.

Here's a screenshot of AS SSD. Just click on the images if you want to see them larger.

And one of CrystalDiskMark

 

[a4mula]

I've never heard of a RAMDisk effecting microstutter issues. I can see how it'd speed up texture caching for files coming from the storage subsystem, but I'm not really sure how it would change the Alternate Frame Rendering micro-stutter associated with crossfire/sli setups. This is more of a synchronization issue where one card is rendering a screen faster than the second creating a lag in the output.

Wow, those are some smokingly fast reads and writes. I'm suprised you didn't choke the Marvell controller. Are you running those off a discrete RAID controller?

Either way, thanks for posting your results. I'll definitely be giving that program a look.

Now I'm curious if you could use that as a pre-buffer for SRT. A tiered approach at caching. I'm weary of my current SSDs, just the constant buzzing in the back of my head about write thrashing, space issues, and the pain that setting SSDs up right the first time really has me leaning towards the install and forget nature of it.

Thanks again, really. Very insightful. Great rig also.

 

[Idonno]

I've never heard of a RAMDisk effecting microstutter issues. I can see how it'd speed up texture caching for files coming from the storage subsystem, but I'm not really sure how it would change the Alternate Frame Rendering micro-stutter associated with crossfire/sli setups. This is more of a synchronization issue where one card is rendering a screen faster than the second creating a lag in the output.

Wow, those are some smokingly fast reads and writes. I'm suprised you didn't choke the Marvell controller. Are you running those off a discrete RAID controller?

I hear what your saying about micro-stutter which is why I took a year to try that solution. I really don't know exactly why it worked only that some others claimed it did and eventually as a last resort i tried it. All I can say for sure is it completely solved the problem.

No discrete RAID controller, Just the on-board Intel controllers. I use the Marvell controllers for my optical drives only (not to fond of my 1st gen Marvell controllers).

The app (SuperSpeed SuperCache) seems to be very well written. With read every thing you need to really speed things up gets cached and with write there is an option for "lazy Write" which can delay a write (keep it in ram) for anywhere from 1-15 seconds (you choose) I have it set to 5 sec. This really speeds up writes but could be especially dangerous for raid 0 without a good battery back-up.

So far it seems to be a really good app and THX for the PC kudos. Yours isn't to shabby either

 

[a4mula]

No discrete RAID controller, Just the on-board Intel controllers. I use the Marvell controllers for my optical drives only (not to fond of my 1st gen Marvell controllers).

I feel you on the Marvell controller. So.. that means you're running ICH10R 3Gb/s? I was under the impression it capped at 660MB/s. Interesting results. Not sure how to look at it, transfer rates from the QPI are exponentially higher, so this could be factoring not only transfer rates of the RamDisk to SSD (ICH10R), but also CPU to RamDisk (QPI) which could skew the results.

Hmm, I dunno. Will have to consider what's going on here more. At some point the data has to pass through ICH10R which is going to be completely saturated creating a bottleneck. I'd really love to see this setup on an Areca 1880 or at a minimum a decent pci-e SATA 6Gb/s card.

 

[RetiredChief]

Ramdrive performance is higher, ie Seq reads in the area of 5000. Other values are also higher. Currently on vacation (LA) so can not post a screen shot. With Ramdrive the Sata controller is irrelevant as Performance is a function of memory

 

[Idonno]

Ramdrive performance is higher, ie Seq reads in the area of 5000. Other values are also higher. Currently on vacation (LA) so can not post a screen shot. With Ramdrive the Sata controller is irrelevant as Performance is a function of memory

Yea, but your comparing apples to oranges.

If I was just posting screen shots of a RamCache in action I think the speeds would be similar since they both use my ram.

This is my 4GB RamDisk

The screen shots I posted earlier were of my 240GB C drive assisted by a 8GB RamCache which is very different and much more practical than a RamDisk in many ways.

A RamDisk for the purpose of a C drive would not be practical anyway, unless you only wanted a very small drive and you never planned on shutting down your PC. It would take far to long and the first time you lost power or had to do a hard shutdown your OS would be toast.

 

[RetiredChief]

@ Idonno. Got you.
However Benchmark programs are not very representative of performance for large "cached" HDD as real life performance is highly dependent on algorthium that does the cache and also how repetitive file reads are.

 

[Idonno]

@ Idonno. Got you.
However Benchmark programs are not very representative of performance for large "cached" HDD as real life performance is highly dependent on algorthium that does the cache and also how repetitive file reads are.

That may be true, but unlike my opinion ("It definitely makes a bigger difference than I thought possible"), benchmarks do offer real evidence.

It's not a "large "cached" HDD", It is a fairly small hard drive (240GB) assisted by a very large cache (8GB RamCache)

While it's true an 8GB cache would not offer anywhere near as much benefit on large sustained Reads/Writes of 8GBs and greater, the speed of your OS and programs are almost entirely dependent on much smaller Reads/Writes.
My over-all access time seems to have been improved as well.

I personally give this program an A+. At $79 (I think) it's not cheap, however in my opinion It offers me a better real life performance increase than adding another 1 or 2 SSD's to my existing raid 0 array so the price is worth it.

Will it help you with a large file transfer, say maybe a 40GB blu-Ray? Not so much. But even if you had 5 Sata III SSD's in raid 0, unless you had somewhere just as fast to transfer it to or from that wouldn't help you either.

So if I do decide to purchase it, I think it will be money well spent. Right now My OS feels incredibly snappy! I like it, but the only way for you to know is to try it. It's free for 14 days.

Hmm, I dunno. Will have to consider what's going on here more. At some point the data has to pass through ICH10R which is going to be completely saturated creating a bottleneck. I'd really love to see this setup on an Areca 1880 or at a minimum a decent pci-e SATA 6Gb/s card.

That's true but as long as the read/write activity isn't sustained over too long a period the RamCache should be able to buffer this. A real limiting factor here is the size you choose for your RamCache and your available ram, although a fast raid card or a fast RevoDrive would certainly improve the RamCache's ability to buffer the Read/Writes.

 

[RetiredChief]

^ "got you" was a poor choice of words - should have said Understand you.
Always nice to have a 2nd opinion. And with a free 14 day trial, it's always worth a shot.

 

[Idonno]

^ "got you" was a poor choice of words - should have said Understand you.
Always nice to have a 2nd opinion. And with a free 14 day trial, it's always worth a shot.

That's OK even though It could be taken a few different ways I knew what you meant.

And yes, you should give it a try. It's very easy to implement and even if you decide you don't want it, it should be kind of fun anyway.

 

[sminlal]

IMHO using main memory as a RAM drive is largely a waste of time unless you have a very specific need and have confirmed that the end performance really is better. And I'm not talking about synthetic benchmarks, I'm talking about timing some activity (like playing a game or editing a video) to see if a RAM cache actually makes a measurable difference.

A problem with RAM drives is that they loose their data when powered off - this means that you need to load them up with data, typically from a hard drive, when the system is powered up anyway. When you combine that with the fact that Windows does a pretty good job of caching disk activity in unused RAM anyway, a RAM drive doesn't really buy you very much.

Take temp files, for example. When a program writes to a temp file to a hard drive, Windows caches the writes - so the program sees its output operations complete instantly while Windows does "lazy writes" in the background to dump the data to the drive. Then when the program comes back to read the data again, Windows supplies it from the cache and again the I/Os complete instantly.

The only instance I can see in which a RAM drive would be beneficial is if you have specific critical data you want to keep in RAM even though you're doing heavy reading and writing of other files at the same time to the extent that your critical data gets kicked out of the cache. In effect the RAM cache gives you the choice of forcing some data to remain in RAM at the expense of other data, something that you don't have control over otherwise.

But that's not really a scenario that applies to most people.

Having said all that, the original premise - buy lots of RAM for caching - still applies. It's cheap, and it really does make a difference when you're going a lot of repetitive file accesses, even if you just let Windows use it for caching.

 

[Idonno]

@sminlal You seem to be getting RamDrive & Ram Cache mixed up. While they do have very real similarity's they are not the same and they serve very different purposes.

Windows only does a pretty good job of caching disk activity in unused RAM when you have less than about 12 GB's of total system ram. At this time windows is still not written to take advantage of the larger amounts of ram that the newer motherboards are capable of.

A very good example is if you have 24-64GB's of ram and set your Paging file to "let windows Choose" instead of using ram or even offering that as a alternative windows will set a fairly large Paging file on all of your hard drives.

In fact whether you have 12 or 24 GB's of ram windows will use approximately the same amount. This isn't because at 12GB's windows is already using the optimal amount. This is because windows has not yet been written to take advantage of the larger amounts of ram recently available to the average user.

"synthetic benchmarks" while I do agree that they don't ALWAYS properly represent ALL real life usage. They still are one of the best tools for checking hardware performance that we have. For instance if you check the users configuration in any of the top PC benchmark programs that store these statistics you will not find a single crappy PC in any of the top slots, similarly all you will find at the bottom are crappy PC's and PC's with hardware issues.

Your statement:

Having said all that, the original premise - buy lots of RAM for caching - still applies. It's cheap, and it really does make a difference when you're going a lot of repetitive file accesses, even if you just let Windows use it for caching.

Is true if by lots of ram you mean 8 or 12GB. however by today's standards with a few LGA 2011 motherboards capable of 128GB's and still more capable of 64GB's of ram, 12GB's is at least starting to seem rather small. And I assure you without a program like SuperSpeed SuperCache to assist windows won't use all that extra ram for caching or anything else.

Maybe win 8, we'll see, but certainly not 7-64 or any previous windows.

P.S. I just did a little test: I created a 4.36 GB ISO image file from DVD files. Total Time: 36 sec.

 

[sminlal]

@sminlal You seem to be getting RamDrive & Ram Cache mixed up. While they do have very real similarity's they are not the same and they serve very different purposes.

No, I'm not mixing them up, what I'm saying is that since Windows' RAM cache keeps a copy of the data you're using in RAM anyway, using a RAMDrive to manually load stuff into RAM doesn't really give you any particular advantage except in certain specific scenarios.

A very good example is if you have 24-64GB's of ram and set your Paging file to "let windows Choose" instead of using ram or even offering that as a alternative windows will set a fairly large Paging file on all of your hard drives. In fact whether you have 12 or 24 GB's of ram windows will use approximately the same amount.

I'm not sure why you're discussing the page file size here - it really doesn't have anything to do with caching file accesses in RAM. In fact almost everyone with 12GB or more of RAM (and even less) would probably be better off simply disabling their page file altogether. The "classic" page file sizing rule of 1.5X your RAM size makes no sense whatsoever when you get up into these kinds of large RAM sizes, and I'm sure Microsoft was smart enough to put some sort of cap on the default maximum page file size. I've run with no page file for a few years now and my system works just great.

When you have, say, 24GB of RAM there are only three reasons I'm aware of why Windows wouldn't be using it for file caching:

1) if it's being used by some other program,

2) if the program doing the file accessing is bypassing the cache (for example, backup or integrity checking programs often do this), or

3) if you haven't actually accessed 24GB's worth of data in your files yet. That's a lot of space, and it takes quite a bit of file activity to actually access that much data. It's only when you start copying around huge files like movies that it starts to take advantage of that much RAM cache. And even then, you only get the benefit the second or subsequent times you read the file (although write caching is an immediate benefit).

 

[Idonno]

No, I'm not mixing them up,

In that case, I apologize for telling you what you seem to think instead of asking you what you thought/meant. That was rude and that very thing has pissed me off in the past as well. I'm sorry!
But for the sake of fairness, if you re-read your post I think you might see how at least I might have jumped to that conclusion.

I'm not sure why you're discussing the page file size here - it really doesn't have anything to do with caching file accesses in RAM.

Your right it doesn't, however it is a perfect example of windows not making use of excessive ram

I'm sure Microsoft was smart enough to put some sort of cap on the default maximum page file size.

At 24GB's of ram I haven't seen it yet. Maybe someone with more ram can chime in here.

I've run with no page file for a few years now and my system works just great.

That's great. I tried it for a while and for the most part everything was ok. However it should be noted that there are some applications that require a page file and after I created a 4GB RamDisk and dedicated it solely for my pagefile things ran noticeably smoother. (yet another reason to bring up pagefile)

When you have, say, 24GB of RAM there are only three reasons I'm aware of why Windows wouldn't be using it for file caching

I'm not going to even try to argue the finer points as to why windows doesn't use excessive ram for ANYTHING, only that from personal experience it doesn't! Even with 53 instances of WinRar running at the same time with 24GB's of ram the most it used was a little over 8GB's. If you want to use excessive ram (over 12GB's of system ram) you need to use an app that is specifically designed to take advantage of large amounts of ram.

I am not speaking of the way I think things should be. I am speaking from experience about the way I have found things to be.

I have used 24Gb's of ram for over 1yr now. RamDisk for 1 month and SuperSpeed SuperCache (RamCache) for just under a week. I see value in both especially RamCache. I came to these conclusions through experience with these app's and the noticeable difference in performance they provided. NOT because some benchmark told me my system was now faster, all the benchmark did (for me) was point out what was already obvious.

Lastly and most important MERRY CHRISTMAS to all

 

[sminlal]

Even with 53 instances of WinRar running at the same time with 24GB's of ram the most it used was a little over 8GB's.

That's not a limitation of Windows, it's how WinRar works. When you're copying files around you really can't get any faster than using double buffering for the input and output files - that way you always have an I/O outstanding to each drive and the CPU won't be a bottleneck. It doesn't take very much RAM to do that, only a few megabytes per copy thread.

Windows will very happily allocate tons of RAM to a program if it asks for it. When I decided to run without a pagefile I wrote a program which sat around allocating memory until the system ran out of it just to understand what would happen. Windows didn't have any qualms about granting as much memory to my program as it asked for, promptly ran out of RAM, and displayed a dialogue box which offered to cancel the offender. Once the wayward program was cancelled, the system carried on as if nothing had happened.

The memory manager in 64-bit Windows 7 is exactly the same one that's used in Windows Server 2008 R2. The only difference is the fact that some artificial caps on memory size are removed from the server version, and the default settings favour background services over foreground GUI programs. You can be sure that Microsoft would have some very unhappy corporate customers if Windows didn't let them fully utilize the huge amounts of very expensive ECC server memory they cram into their servers.

it should be noted that there are some applications that require a page file and after I created a 4GB RamDisk and dedicated it solely for my pagefile things ran noticeably smoother.

Yes, I had that experience with Photoshop V6.0. It's one of the reasons I upgraded to CS4, which works very happily without a pagefile. Those applications are, fortunately, getting fewer and farther between.

I agree that if you've got one of those programs then yes, you do need to create a pagefile. But it doesn't have to be a huge file, you can create tiny little 10MB pagefile and the system and the wayward program will both work just fine. In fact with the kind of RAM we're talking about, the system isn't going to be putting anything significant into the pagefile anyway, so you're pretty unlikely to see any noticeable performance degradation if you just let the system create it on the OS drive, even it it's a hard disk. The one thing to watch out for is if the wayward program is using the pagefile location to decide where to put its work files - in that case the location of the pagefile does matter, but only indirectly.

 

[Idonno]

WinRar was just one of many possible examples. And I really don't see the point in arguing with you any more. You say things like:"Windows will very happily allocate tons of RAM to a program if it asks for it" OK so whats your point?

Because I said "If you want to use excessive ram (over 12GB's of system ram) you need to use an app that is specifically designed to take advantage of large amounts of ram." Why? Because windows wont allocate large amounts of ram for ANYTHING unless it is asked to by "an app that is specifically designed to take advantage of large amounts of ram." Wow, didn't I say that before? It sounds kind of like what you said only with slightly different words!

So go and try RamDisk for a pagefile or RamCache for your OS drive (you might want to get some more ram first) then get back to me. Your credibility then will be greatly enhanced but right now you sound kind of like one of history's naysayers. Just so you know, the world isn't flat, more than 15mph on a train won't result in a heart attack, man can fly even though god didn't give him wings and yes man can and has walked on the moon.

The point is, myself and quite a few others have tried RamDisk and RamCache and have realized the benefits first hand. You on the other-hand seem so set in your belief that they provide very little benefit, you will not even listen to people that have or god forbid try it yourself.

That leaves you with very little credibility on this issue and quite frankly I am unwilling to waste anymore of my time arguing with you! Try it or don't. I don't care.

 

[a4mula]

Thank you again for posting your results and experience with the product Idonno. I don't claim to be technical enough to intelligently contribute to the debate but I can honestly say that at $79 dollars and with a 2 week free trial it will be something that will at least be examined in my new build.

 

[Idonno]

Thank you again for posting your results and experience with the product Idonno. I don't claim to be technical enough to intelligently contribute to the debate but I can honestly say that at $79 dollars and with a 2 week free trial it will be something that will at least be examined in my new build.

Thanks a4mula, I'm glad you found the information at least provocative. I was starting to think I made a mistake by even posting here but I guess as long as a few found my info interesting I didn't.

 

[sminlal]

Because I said "If you want to use excessive ram (over 12GB's of system ram) you need to use an app that is specifically designed to take advantage of large amounts of ram." Why? Because windows wont allocate large amounts of ram for ANYTHING unless it is asked to by "an app that is specifically designed to take advantage of large amounts of ram." Wow, didn't I say that before? It sounds kind of like what you said only with slightly different words!

Actually, what started me out on this was your first reply to my first post, in which you said:

At this time windows is still not written to take advantage of the larger amounts of ram that the newer motherboards are capable of.

My point is that Windows has no such limitation. If you've got the memory, Windows will use as much of it as it needs for file caching and it will let programs use as much as they need. WinRAR simply doesn't need a lot of memory, so it's a mistake to use it as an example of supposed problems with Windows memory management. Most other programs are the same. It's only extremely memory-intensive programs such as video editing, database serving and the like which can actually do something useful with that kind of memory.

Saying that Windows has a memory management problem because programs don't allocate a lot of memory is like blaming GM for low ridership when a transit company uses their 40-seat buses on a route that only gets a few customers.

 

[Idonno]

Nope I'm not going to do it, I could......... no, I'm just not going to!